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Sold SPR modified TBI

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Paul
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I have a rebuild GM TBI off my ‘90 Chevy Blazer from SPR performance. It’s been modified for 650 cfm, from what I’ve read it’ll support around 400hp.

https://www.ebay.com/itm/46mm-PORTE...837306?hash=item3d963196ba:g:mpwAAOSw2xRYWVJj

I converted to carb without ever installing this unit. I have the receipt which will be shipped along with the TBI. Asking $400 shipped UPS to the continental US. Will ship for additional cost to anywhere.
Offers considered. Will trade for parts+cash as well, currently looking for an aluminum dash bezel, would like a tach gauge cluster, other offers considered.

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ZooMad75

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Hey how would this TBI work on a dead stock 350 in a '94 K1500? Reason I ask is our owner's son has that truck (it was his first) and he's set on keeping it. We swapped in a new goodwrench 350 last year with a TBI we went through and rebuilt but it's obvious to me the throttle shafts are worn and we are getting vacuum leaks that is causing it to stumble intermittently. Prior to the engine swap we used a Holley replacement TBI and that turned into a bigger nightmare than we bargained for, hence putting a stock TBI back on it when the engine was replaced.

Honestly I'm tired of listening to the guy bitch about it and just want to fix it once and for all. I haven't really researched any outfits that rebuild these until I saw your ad. But made me think about it.
 

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Paul
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I read a build thread here that talked about it making a noticeable difference, I can’t for the life of me remember who it was. I’ll do some searching.

I have no first hand experience in it though.
 

1-ton

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I read a build thread here that talked about it making a noticeable difference, I can’t for the life of me remember who it was. I’ll do some searching.

I have no first hand experience in it though.

I have a TBI that was modified by Vic Morse the same as yours. I would not say it makes a big difference at lower RPM's. I can say that my Vic Morse TBI does run like a brand new TBI with no issues at all.

full
 

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Paul
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No reasonable offer will be turned down, someone take this off of my hands so it’s not rolling around my shop!
 

6872xtc

make mine modified
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Hopefully my post helps.


I ended up installing a TBI from SPR on a buddy's stock 350 for him. I didn't notice any great improvement on that engine, but it worked perfectly. I then ended up with it later and put it on my tired 350 in a '95 truck. I did fix some of the issues that I had with the original, worn unit. It does pull better in the mid range and up, but that truck doesn't see that too often.
So I would trust another unit built by SPR.
 

1-ton

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"Prior to the engine swap we used a Holley replacement TBI and that turned into a bigger nightmare than we bargained for".

The reason the Holley replacement TBI did not work on a small block is because the Holley units are designed for a big block and not a small block. The holley TBI's have 2" diameter bores that match up with the big block 2" diameter intake manifold bore, and the small block has 1-11/16" intake manifold bore. Fuel will go splashing and puddling all over the place if the TBI bore and intake manifold bore do not match up. I had my TBI intake manifold port bored out 1/8", in order to match up with the 1/8" increase in bore size that Vic Morse bored out my TBI to. This 1/8" increase in bore size is where the increase in CFM comes from when SPR or Vic modifies factory TBI's.

SPR and Vic Morse are the leaders in ultimate mod, TBI venturi boring, injector flow matching, and throttle shaft re-bushing for TBI's.

SPR is where to go on the East coast, and Vic Morse is the place to go on the West coast.
 
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imiceman44

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"Prior to the engine swap we used a Holley replacement TBI and that turned into a bigger nightmare than we bargained for".

The reason the Holley replacement TBI did not work on a small block is because the Holley units are designed for a big block and not a small block. The holley TBI's have 2" diameter bores that match up with the big block 2" diameter intake manifold bore, and the small block has 1-11/16" intake manifold bore. Fuel will go splashing and puddling all over the place if the TBI bore and intake manifold bore do not match up. I had my TBI intake manifold port bored out 1/8", in order to match up with the 1/8" increase in bore size that Vic Morse bored out my TBI to. This 1/8" increase in bore size is where the increase in CFM comes from when SPR or Vic modifies factory TBI's.

SPR and Vic Morse are the leaders in ultimate mod, TBI venturi boring, injector flow matching, and throttle shaft re-bushing for TBI's.

SPR is where to go on the East coast, and Vic Morse is the place to go on the West coast.
Parts matching is always key.
Many people don't know that and think I can slap a part on and everything should work. Research is very important before you put down the $$$.
Hopefully whoever is buying this benefits from this discussion
 
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